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Python Python Collections (2016, retired 2019) Sets Set Math

Sean Flanagan
Sean Flanagan
33,235 Points
Posted by Sean Flanagan
Sean Flanagan
33,235 Points

Why won't this work?

Hi.

I thought that .intersection was the method that yielded the common items between two sets, yet that doesn't seem to have worked here.

sets.py 
COURSES = {
    "Python Basics": {"Python", "functions", "variables",
                      "booleans", "integers", "floats",
                      "arrays", "strings", "exceptions",
                      "conditions", "input", "loops"},
    "Java Basics": {"Java", "strings", "variables",
                    "input", "exceptions", "integers",
                    "booleans", "loops"},
    "PHP Basics": {"PHP", "variables", "conditions",
                   "integers", "floats", "strings",
                   "booleans", "HTML"},
    "Ruby Basics": {"Ruby", "strings", "floats",
                    "integers", "conditions",
                    "functions", "input"}
}

def covers(set_of_topics):
    return set_of_topics.intersection(COURSES)

1 Answer

ursaminor
ursaminor
11,271 Points
ursaminor
ursaminor
11,271 Points

You're returning the intersection between topics (a set) and COURSES (a dictionary). You need to get the intersection of topics with the topics in COURSES (its values) and return the keys (course names) in a list.